Harmony School Tile Failure

Removal of exterior tiles to be replaced.
Section of tile that fell from the wall.
Patches of mortar holding tile to wall.
Patches of mortar holding tile to wall.
Micro structure of cement paste used to bond tile to wall. (SEM photo)
Micro structure of cement paste used to bond tile to wall. (SEM photo)
Micro structure of cement paste used to bond tile to wall. (SEM photo)

Falling Tiles at an On-going Construction Site, Harmony Public School Houston, Texas.

 
An almost completed exterior wall tiling of one of a new public School building was put on hold due to falling of some tiles from the wall. C3S, Inc. (C3S) was contracted to determine the probable cause(s) of the problem. A representative of C3S visited the site and interviewed masons working on the building. Three different cementitious materials being used were submitted for evaluation. A few potential sources likely to cause the problem were pointed out including a cementitious product with relatively high admixture content and high air content.